Yes, it was meant as humor. And FWIW, I consider myself an audiophile too, but an old-school audiophile-engineer, which means designing products for performance that can be both objectively measured and unequivocally heard by non-audiophiles.
I've spent more than 40 years designing state-of-the-art electronic products so I do find it humorous that "experts" whose engineering expertise ends at swapping CPU's on a PC motherboard think they can increase the REAL performance of an intricately designed system with a different brand of goop. We (engineers) do make mistakes, most often when implementing new unproven technologies, but selecting thermal paste isn't really in that category. I suspect it would have taken a significantly bigger change in the product design to reliably get more performance from the chosen CPU. And I'm quite comfortable that the Apple engineers, working from the Intel engineer's specs, are operating the CPU safely.